Burnishing machine



F. M. FURBER.

BURNISHING MACHINE.

APPLICATION man AUG-5, 19w.

1,404,19 Patented Jan. 24,1922;

W l/ EA/ 70 UNITED STATES PATENT OFFICE.

FREDERICK M. FUR-BER, OF REVERE, MASSACHUSETTS, ASSIGNOR TO UNITED SHOE MACHINERY CORPORATION, OF. PATERSON, NEW JERSEY, A CORPORATION OF NEW I annsn'z.

Specification of Letters Patent.

BURNISHING MACHINE.

Patented Jan. 2st, 1922.

Application filed August 5, 1918. erial No. 248,345.

ing of tools and is disclosedby way of illustration as embodied in a burnishing machine for setting the sole edgesof boots and shoes. Machines for burnlshing soleedges, com

monlyknownas edge setters, are generally provided with a moving tool profile to the sole edge desired and moved rapidly over the sole edge in order to burnish it. For the performance of good work it is necessary to heat these tools to a relatively high temperature, for example, to'a temperature of approximately 375 F The most com mon means for heating the tools is agas flame.v It has as a practical matter bee: necessary to use a luminous and therefore a smoky gas flamev for two reasons principally: In the first place, a blue flame form a Bunsen burner is so nearly invisible that the operator is liable to injure himself with it, and in the second place, ithas proved very dii'licult as a practical matter to keep a Very small blue flame alive in a shoe factory operating room. A smoky flame, on the other hand, deposits soot onthe tool and more or less damage to the shoe results.

It has been proposed to use electricity for heating edge setting'tools because of its convenience in use and the absolute cleanliness obtainableb'y its use. Several difficulties have interfered with the universal commercial acceptance of this heating agent. For example, if a resistance heating unit is suspended upon thenioving tool carrier, the conveyance of the current to and from the unit involves a ditfieult matter of design andthc unit itself and its connections are in continual danger due to the rapid .movement of the parts containing them. If theunit is suspended upon a fixed 7 part of the frame, it is very difiicult to convey heat enough to the tool with any degree whatever of economy in consumption of elec tric energy.

It is aprincipal object of my invention to provide for the electric heating of tools in a manner which shall not be subject to the above described and other disadvantages. In carrying out my invention. I have provided for heating the tools by a blast of electrica ly heated gas, preferably air. In this way, all the advantages of electric heating are retained and none of the disadvantages are encountered since the electric unit can be mounted upon the stationary frame of the machine and therefore involves no troublesome or expensive designing, and the air heated by it can be conveyed from a small pipe to the vicinity of the tool with all the convenience of any gas flame construction. In this aspect of-it, an important feature of the invention is, therefore,

a novel organization of burnishing means and electrical heating means comprising an electrical unit arranged to heat a current of gas which is conveyed to the tool.

Another important feature of the invention by which a very considerable economy in the use of electric energy is effected cons'ists in producing an initial rise in tcmpen ature of the air by using the air in the room as a heating agent and thus introducing the air to the unit at a substantially higher temperature than would have been possible if it had been taken directly from the supply pipe. I found that a substantial pressure in the air supply was necessary in .order to keep the stream of hot air moving satisfactorily, this air stream being of small cross-section and consequently subject to considerable skin friction in the pipe which carried it. lVhen this air under pressure was permitted to expand in the vicinity of the electric unit, its temperature immediately dropped 20 to 30 degrees because the expansion was substantially adiabatic. The air was then warmed by its passage over the unit. I found that by allowing the air to expand in a coil in thermal communication with the air of the room its temperature: would be raised substantially to the room temperature in passing through the coil and that if it were then introduced to the electric unit, the same unit would produce a delivery temperature some 25 or 30 degrees F. higher than if the air were expanded directly into the unit chamber. In this aspect of the invention I produce what is virtually isothermal expansion independently ofthe heat unit, and in the embodiment illustrated T effect this by expanding the air into a chamber in thermal communication with the surrounding air. A substantially smaller unit can therefore be used in heating a given volume of air per minute to a given temperature by virtue of this feature of the head carrying a plurality of edge setting toois, a shank iron and a forepart iron. As is well known, it is customary to mount these tools side byside upon a single axis and to turn the axis in order to interchange the tools in operative position so that the. operator may use one after the other in setting the sole edge. ,I have provided a tool carrying head having a conduit for conveying the air directly to'the tool'into which conduit the air may be conveyed from the electric unit. In the machine shown each tool is provided with an individual conduit, the receiving end of which is brought into communication with the outlet from the unit chamber as the tool is brought into operative position. Such structure is an important feature of the invention. The structure described has another very important advantage which is that the tool supplying conduit is heated by the passage of the air through it and conducts heat through-the tool mounting to the tool. The tool therefore acquiresheat from the air both by conduction and by convection. Thisarrangement secures a very important and considerable economy in the expenditure of electrical energy over any system involving the mere lilowing of the hotair against the tool from anozzle analogous to the gas flame construction.

The drawing shows a side view 01" anedge setting machine embodying the invention.

The pulley 10, driven .by the belt 12, through mechanism in a casing 15L designed to transform" movement of rotation into movement of oscillation, oscillates the shaft '16 in the bearings 17 carrying the head '18. The mechanism in the casing '14 may be of any desired type, for instance, such as is shown in my Patent 1,268,832, June 11, 1918. The head 18 is provided with a tool carrier 20 arranged to carry two tools 22 and 24:.

The tool head 2O may be rotated 180 in is made of the heat content of the air.

order to interchange the tools in operative position by any desired means, preferably bythe means shown in my application Ser. No. 93,912, filed Apr. 27, 1916, to which reference may be made. The interchanging means, broadly speaking, comprises a lever 26 operatedby pushing the shoe in the hand of the operator against its end at28, the said lever carrying a threaded screw-driver blade 30 engaging in a slot 32 when the lever is operated. The screw-threads on the blade 30 rotate the blade and the head 20. v The specific tool interchanging means constitutes no part of the present invention and need not be further described. 7

The tool head 20 carries two sleeves 34 and 36 which receive spindles mounted on the tools 22 and 24. These spindles are notched, and springs 38 projecting through holes 40 in the sleeves engage the notches and hold the tools in posit-ion. Fastened integrally to thesleeves 34 and 36 are two little conduits 4:2 and d4, respectively, open at the top, extending downwardly parallel to the tool spindles, and curvedaround to open directly against the tools. Heated air introduced into the upperendsofthe con duits will therefore pass through them and blow against the tools, giving up heat meanwhile to the conduit walls which conduct it through the sleeves 34 and 36 to the tools.

The tools are thus heated both by -conduc-.

tion and convection, and every economic Inge e two conduits are symmetrically arranged relatively to the axis of the tool holder 20. Therefore the conduit appurtenant to the tool in use at any givenltime (the right hand tool as shown in-the drawing) will always be in the position occupied by the conduit 44 in the drawing. Mounted upon the'main frame of the machine is a heat insulating casing 46 enclosing a coil 4-8 which in turn encloses, in the construction shown, an'electrio unit 50. One end of the coil iS exhausts through a pipe 52 arranged with its end directly over and in close relation to the upper end of the conduit appurtenant to the tool operating at any given time. The other end of the coil communicates with a coil 5450f any desired length theotherend of which communicates througha-valve 56 with a pipe 58 carrylng a r under any desired: pressurej I have found that the ordinary compressed a1r system of a factory constitutes a suitablesonrce of air supply.

The air'in expanding through the valves 56 'flows intothe coil 5a where the drop in temperature resulting from the nearly ple, 375 to e00 degreBS Fahrenheit Th end of the pipe 52 registers with the end of the conduit appurtenant to the operating tool and the air, as it passes through the conduit, blows out upon the tool and also heats the sleeve and tool by conducted heat as described above. The stroke of the tool is, in machines of this type perhaps 9; inch, and the upper end of the conduit is of sufficient spread to register with the end of the pipe 52, whatever the position of the tool in its swing.

The heated air is directed against that lateral face of the tool farthest from the operator, who holds the shoe upper toward him as he sets the sole edge The heated air thus blows out parallel to the tread face of the sole, does not contact with itsufliciently to affect its temperature 'injuriously, and does not reach the rest of the work at all. This feature of theinv'ention is of importance in connection with lowering the temperature of a tool by a cold blast as well as raising it as herein shown.

The machine contains a finger hook 60 which is hollow and is provided with the ordinary gas burner 62 which may be used if electrical energy is not obtainable. For further description of the finger hook shown,

reference may be made to my application Ser. No. 93,912, above referred to, as the said hook forms no part of the present invention. It will be noticed that the conduits 42 and 14: are arranged above the tools which they heat rather than below them, and are therefore entirely out of the way of the operator in manipulating the shoe, the tools and the finger hook.

Having described my invention, what I claim as new and desire to secure by Let ters Patent of the United States is 1. In a machine of the class described, a tool, a gas casing, an electric unit arranged to heat the gas in said casing, means for supplying gas to the casing, and means for conveying the heated gas from the casing to the tool in order to heat the tool, constructed and arranged to protect the work from direct contact with the heated 2. In a machine of the class described, a tool, a source of compressed gas, means for effecting substantially isothermal expansion of the gas, and means for heating the isotherm-ally expanded gas and conveying it to the tool.

In a machine of the class described, a tool, a source of compressed gas, means for effecting substantially isothermal expansion of the gas, and independent means for heating the isothermally expanded gas and conveying it to the tool.

4. In a machine of the class described, a tool, a source of compressed air. means effecting substantially isothermal e uision of the air from the source, an electric unit, means for bringing-the air in contact with the unit to heat the air, andnleans for conveying the heated air to the tool.

5. In a machine of the class described, a source of compressed air, an expansion chamber for the air in thermal communication with the air of the room, a heating coil communicating with said chamber, means for heating the coil, and a pipe arranged to conduct air from the coil to the tool.

6. In amachinc of the class described, a tool, a channel adjacent to the tool having its walls in thermal communication with the tool, said channel also having an opening opposite the tool whereby heated air passing through the channel will communicate heat to the tool by both convection and conduction, and means for forcing heated air through the channel.

7. In a machine of the class described, a tool carrier, a plurality of tools mounted thereon. a channel in thermal communication with each tool, mechanism for interchanging the tools to facilitate the performance of different operations at the same operative position, an air pipe having its end registering with the end of the channel ap purtenant to the tool in operative position, and means for forcing heated air through the pipe.

8. In a machine of the class described, a tool carrier, a rotatable spindle in the carrier, a plurality of tools mounted on the spindle, a conduit mounted on the spindle appurtenant to each tool, said tools and conduits being symmetrical relatively to the axis of the spindle, said spindle being rotatable to present different tools in operative position, and a. pipe arranged to deliver heated air into the conduit appurtenant to the tool in operative position.

9. In a machine of the class described, a tool carrier, a tool mounted on the carrier, a conduit embedded in the carrier having an opening opposite the tool, and means for supplying heated air to the conduit whereby the heated air will be forced against the tool through the opening and will also communicate heat to the tool by conduction through the walls of the conduit.

10. That improvement in the art of heating tools which consists in taking air from a source of compressed air, substantially isothermally expanding the air, heating the iso'thermally expanded air to operating temperature, and applying it to the tool.

11. That improvement in the art of heating tools which consists in expanding the air from a source of compressed air supplying heat to correct the drop in temperature due to adiabatic expansion, heating the air to operating temperature, and applying it to the tool.

12. In an edge setting machine, a rotatable spindle, a head at the lower end thereof, a tool carrying holder at the lower end of the spindle, an edge setting iron carried by said holder, and a conduit mounted on the holder and extending downwardly to a point opposite the iron in such manner that it lies entirely above the space in which the operator manipulates the shoe, arranged to convey heated air to the iron.

13. In a machine of the class described, a

, tool, a source of compressed gas, a receptacle air,'allowing the expanded air to absorb a substantial quantity of heat from. the atmosphere to raise its temperature after the drop due to the expansion, heating'th'eexpanded and warmed air to operating temperature, and applying it to the tool.

. 15. In a machine of the class described, a source of compressed air, an expansion chamber for the gasinthermal communication with its surroundings whereby the gas may absorb heat from its surroundings to offset the drop intemperature due to expansion, a heating chamber constructed and arranged to heat the expanded and warmed gas to operating temperature, and means for conducting the gas-to thetool.

In testimony whereof I- have signed my name to this specification. v

FREDERICK M. FURBER, 

